Retaining HIV-positive individuals in care and on antiretroviral therapy (ART) is crucial to maximize the clinical benefits of ART and to reduce HIV transmission. However, retention in care in the U.S. is poor and represents a major challenge in controlling the domestic HIV epidemic. Individuals with mental health and substance use disorders are at high risk for poor retention, and interventions to improve retention in this population are urgently needed. Although mental health and substance use disorders are highly prevalent among HIV-positive individuals, they are under-recognized and frequently undertreated or untreated. The overarching hypothesis for this project is that that patient-reported depressive symptoms and substance use are important predictors of poor retention in care and that a feasible, clinic-based approach for responding to positive screening tests for depressive symptoms and substance use will improve recognition and treatment of depression and substance use, and ultimately retention in HIV care. Three aims will be undertaken: 1) to examine the association between positive screening for depressive symptoms and/or substance use and retention in HIV care using a unique longitudinal dataset including patient-reported outcomes (PROs), clinical data, and payer data 2) to collect qualitative data from HIV clinic patients and personnel to systematically assess the acceptability of strategies to respond to positive screening tests captured through clinic-wide use of screening PROs and 3) to pilot test and generate an estimated effect size for a clinic-based intervention to respond to positive screening for depressive symptoms and/or SU which will include a standardized clinic response and a tailored treatment plan to improve retention in HIV care. My career goal is to be a leader in patient-oriented research focused on improving quality of care and clinical outcomes for HIV-positive patients. To support me in meeting my career goals, I have assembled a mentorship team of senior investigators in different research disciplines, who have a track record of successful research collaborations and mentoring activities. The proposed career development plan contains the training, mentoring, and resources to become a successful independent investigator.